Number of nX3 0..4 arrays of sums of 2X2 subblocks of some (n+1)X4 binary array with rows and columns of the latter in lexicographically nondecreasing order.
A226989
Number of nX3 0..4 arrays of sums of 2X2 subblocks of some (n+1)X4 binary array with rows and columns of the latter in lexicographically nondecreasing order.
Terms
- a(0) =15a(1) =120a(2) =608a(3) =2820a(4) =11325a(5) =40431a(6) =130479a(7) =385529a(8) =1054857a(9) =2699060a(10) =6512038a(11) =14918723a(12) =32643565a(13) =68558024a(14) =138781999a(15) =271754453a(16) =516328629a(17) =954420655a(18) =1720389300a(19) =3030202067a(20) =5224614220a(21) =8832133194a(22) =14659559110a(23) =23920501241
External references
- oeis: A226989